凝灰质砾岩为火山碎屑岩，是火山碎屑岩向沉积岩过渡类型。砾径0.5～5cm，砾石含量40～70%。其中胶结物为凝灰质，砾石为岩屑，分选性差，一般呈半滚圆状，少数为棱角状。 The tuffaceous conglomerate is a pyroclastic rock, which is a transition type from pyroclastic rock to sedimentary rock. The gravel size is 0.5 ~ 5cm, and the gravel content is 40 ~ 70%. Among them, the cement is tufaceous and the gravel is rock debris, with poor separation, generally in a semi-circular shape, a small number in angular shape.